Explore the concept of Invariant Random Subgroups (IRS) in non-Archimedean groups through this 27-minute conference talk by Colin Jahel. Delve into the extension of IRS from locally compact groups to Polish groups, with a focus on closed subgroups of the permutation group of N. Examine the unique characteristics of these IRSs and their relationship to random structures. Learn how this mathematical concept applies to a broader class of groups, expanding the traditional definition. Gain insights into this specialized area of measured group theory as part of the "Théories des groups mesurée/ Measured Group Theory" conference held at the Centre de recherches mathématiques (CRM) in March 2023.